code: def test_forward(self):
      pred_track = np.random.randn(10, 7)
      aflink = TASK_UTILS.build(self.cfg)
      linked_track = aflink.forward(pred_track)
      assert isinstance(linked_track, np.ndarray)
      assert linked_track.shape == (10, 7)
  
file_path: mmdetection/tests/test_models/test_task_modules/test_track/test_aflink.py
imports: from unittest import TestCase
  import numpy
  from mmengine.registry import init_default_scope
  from torch import nn
  from mmdet.registry import TASK_UTILS
label_desc: Use image node_id 3 for calling the TestAppearanceFreeLink obj's underlying member method code with example usage: obj.test_forward() without return types